In the past, electrical connectors have included straight-post type contacts secured perpendicularly in a mounting substrate, such as a printed circuit board (PCB). From an electrical packaging standpoint, such an arrangement of mating elements is generally desirable for electrical components, card edge connectors, backpanel assemblies, and related applications wherein the mating conductors may be at right angles to the mounting substrate without extending beyond the allotted space limitations above the substrate.
It is often desirable to be able to press fit the contacts directly into the mounting substrate rather than soldering them. Certain prior art approaches to press fitted contacts have included only straight-post type contacts having rigid, transversely extending load bearing shoulders for receiving and rigidly withstanding the requisite press fit insertion force from an insertion tool. Moreover, certain straight-post contacts have been designed to be press fitted into bores in a mounting substrate and subsequently covered by an insulative housing. An insulative housing which is removable from around the press fitted contacts provides a means of access to those contacts and facilitates repairability.
When a plug connector having bent contact posts for insertion into printed circuit board holes is inserted into a PCB, it is necessary to apply an insertion force on the upper side of the bends of the contact posts. Specifically, it is desirable to provide an insertion force as precisely as possible in an axial direction of the contact posts. The insertion of such plug connectors is especially problematic when the plug connectors are provided in a plurality of parallel rows, such as, for example, in DIN plug connectors or high pin count (HPC) right angle receptacles and headers. In such connectors, the bent contact posts of the various contact rows, viewed in the direction of insertion, are arranged in overlapping fashion upon leaving the insulating member.
U.S. Pat. No. 4,955,819, Sep. 11, 1990, titled "Plug Connector Having Bent Contact Posts for Insertion Into Printed Circuit Board Holes," discloses a plug connector with bent contact posts in combination with a comb-shaped supplemental part having crosspieces for supporting the contact posts. An insertion tool is also disclosed. This patent is briefly summarized below, as is another patent, namely, U.S. Pat. No. 4,550,962. The drawings of these two patents may advantageously be referred to when reading the following summaries, in which the reference numerals in parentheses refer to the elements depicted in the patent drawings.
In U.S. Pat. No. 4,955,819, the disclosed plug connector includes an insulating member (ref. no. 1) with contact elements (ref. no. 2) contained therein. The contact elements are arranged in a plurality of parallel rows. The contact posts (ref. no. 4) project from the insulating member and are bent at right angles. The contact posts are provided at their ends with an insertion section (ref. no. 7) for fastening and making contact in suitable PCB holes. Lateral flanges (ref. no. 9) on the insulating member are provided with bore holes for securing the plug connector to the PCB.
As shown in FIG. 2, the respective rows of contact posts are in each instance arranged directly under and/or above another row of contact posts. To be able to press the contact posts into the holes of the PCB, an insertion force must be exerted on the individual posts, specifically, on the upper side of the post regions running horizontally. To this end, a comb-like supplemental part (ref. no. 10) is provided. The comb-like part is slipped between the contact posts as shown. Crosspieces (ref. no. 13) are formed in the slots with bearing shoulders (ref. no. 12). Purportedly, a plug connector provided with a supplemental part of this kind may be set up on a printed circuit board with the pin-shaped ends (ref. no. 6) of the posts extending into the circuit board holes such that the insertion sections (ref. no. 7) may be pressed into the holes with the aid of a simple insertion tool (ref. no. 17). The insertion tool includes a flat stamper (ref. no. 18) for acting on the surface (ref. no. 15) of the supplemental part (ref. no. 10). A supporting plate (ref. no. 19) prevents the outer post rows from deflecting or buckling outwardly in the operation of insertion.
U.S. Pat. No. 4,550,962, Nov. 5, 1985, titled "Solderless Electrical Connector Assembly," discloses a solderless electrical connector equipped with inserting segments at the free ends of the contact pins. The inserting segments are inserted into bore holes in the PCB by means of an additional insulating member. An insertion tool having guide ducts formed to receive portions of the contact pins is also disclosed. The disclosed connector is designed to eliminate labor intensive soldering connections and to prevent thermal stresses resulting from the soldering process.
The connector assembly comprises an insulative housing (ref. no. 1) for a multiple contact plug (ref. no. 2). A plurality of contact pins (ref. no. 4), each of which includes a connection post (ref. no. 7) having a connection end (ref. no. 3) and a base portion (ref. no. 4a) extending perpendicularly to the connection post, are mounted on the contact plug in parallel rows. Each of the connection posts of the contact pins is formed with connection ends (ref. no. 3) and stop members (ref. no. 8) defining stop shoulders 8a. The connection posts (ref. no. 7) are shaped for insertion through the bore holes of a PCB. To limit the insertion depth (t), the stop members (ref. no. 8) have a width (b) enlarged relative to the width (q) of the connection posts.
The connector assembly is also provided with an additional plastic housing (ref. no. 9) serving simultaneously as an insertion tool and as an insulating cover. The housing is provided with a comb-like configuration. A plurality of parallel webs or teeth (ref. no. 11) extend from the housing so as to define cutout portions (ref. no. 10). The cutout portions are formed with base portions (ref. no. 10a) and the teeth are formed with free ends (ref. no. 11b), which define complementary shoulders (ref. no. 11a) adapted to bear against the stop shoulders (ref. no. 8a) of the stop members. When it is desired to insert the contact pins into the PCB, the housing (ref. no. 9) is arranged so as to have the contact pins extend within the slots (ref. no. 10). The base portions of the pins will be located beneath the base portions of the slots and the complementary shoulders of the teeth will engage against the stop shoulders of the stop members. Another prior art electrical connector assembly is disclosed in U.S. Pat. No. 4,871,321, Oct. 3, 1989, titled "Electrical Connector." In this assembly, a tool for applying an insertion force to the contact pins does not form a part of the connector assembly and, consequently, a separate cover and stiffener are needed to insulate the contact pins.